Harbin

Harbin needs 3 days: Zhongyang pedestrian street, with European-style architecture from when it was a Russian trading colony, and the Saint Sophia Orthodox church, on one, and the Harbin International Ice and Snow Festival, with monumental ice sculptures lit up at night, for the rest. December-February is the only time for the ice festival, with temperatures dropping below -20°C. It's mid-to-high priced during festival season, when hotel demand spikes. It was built by Russian engineers in the late 19th century for the Trans-Manchurian Railway, which left it with a European architecture unique in China, and its ice festival, with multi-story structures made from blocks cut directly from the frozen Songhua River, is the largest event of its kind in the world.